Cycloheximide suppresses the enhancing effect of sodium arsenite on the clastogenicity of ethyl methanesulphonate.

Post-treatment with sodium arsenite synergistically increases the chromosomal aberrations induced by ethyl methanesulphonate (EMS). We have now provided evidence to show that the enhancing effect of sodium arsenite on the incidence of chromatid breaks and chromatid exchanges induced by EMS in Chinese hamster ovary cells can be suppressed by protein synthesis inhibitors, cycloheximide and puromycin. The most effective time period for cycloheximide or puromycin to suppress the co-clastogenic activity of sodium arsenite was during the middle 6 h in an 18-h incubation time after a 2-h treatment with EMS. The results suggest that the co-clastogenicity of sodium arsenite may require protein synthesis.